The effect of cardiac glycoside storage on growth rate and adult size in the butterflyDanaus chrysippus (L.)

Summary Danaus chrysippus grows faster and attains significantly greater size when fed as a larva on several species of Asclepiadaceae (milkweeds) containing cardiac glycosides than on one which does not.Acknowledgment. I thank Professor D. Schneider and Dr M. Boppré for sending me a sample of butterflies of Kenya stock reared in the Federal Republic of Germany.     

Sex pheromones of the armyworm moth,Spodoptera exempta (Wlk.

Zusammenfassung Es wurden mit gas-chromatographischer Elektroantennogramm-Methode (Z)-9-tetradecenyl-1-acetat und (Z)-9, (E)-12-tetradecadienyl-1-acetat als die Sexuallockstoffe weiblicherSpodoptera exempta (Wlk.) identifiziert.

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Acknowledgment: We are grateful to Mr.C. Rivers, Unit of Insect Virology, University of Oxford Field Station, for supplying insect pupae.     

Inhibition of fading in fluorescence microscopy of fixed cells

Summary Following Hirschfeld et al., dithionite was added to mounting media to inhibit fluorescence fading. Excellent response is reported for fluorescein, acridine orange, 33258 Hoechst, acriflavine, berberine (and ethidium bromide), but not for quinacrine.Acknowledgment. The author is grateful to Dr T. Hirschfeld of Block Engineering, Cambridge, Mass., USA, for an illuminating introduction to his work.     

The influence of 6-OHDA on hypothermia produced by intrahypothalamically-injected carbachol in the pigeon

Summary The involvement of the noradrenergic system in hypothermia induced by intrahypothalamically-injected carbachol (CCh) was studied by depleting hypothalamic noradrenaline (NA) with the catecholamine neurotoxin 6-hydroxydopamine (6-OHDA) and repeating the CCh injections after 6-OHDA treatment. The results suggest that noradrenergic neurons may be involved in hypothermia produced by CCh in the pigeon.     

Detection and distribution of "rutinase+, an enzyme hydrolyzin; rutoside]

125 species were investigated for rutinase. A high enzyme activity was found only in a few genera: Fagopyrum, Rhamnus, Berchemia, Sophora, Datisca and Danae. Lower activity was detected in several Lichens (Parmeliaceae) and diverse plants but is lacking in some specimens. In a number of species containing 3- or 7-rutinosides, no enzyme able to hydrolyse the latter seems to be present.